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Adaptor Hypothesis
The adaptor hypothesis is a theoretical scheme in molecular biology to explain how information encoded in the nucleic acid sequences of messenger RNA (mRNA) is used to specify the amino acids that make up proteins during the process of Translation (biology), translation. It was formulated by Francis Crick in 1955 in an informal publication of the RNA Tie Club, and later elaborated in 1957 along with the central dogma of molecular biology and the sequence hypothesis. It was formally published as an article "On protein synthesis" in 1958. The name "adaptor hypothesis" was given by Sydney Brenner. Crick postulated that there must exist a small molecule to precisely recognise and bind the mRNA sequences while amino acids are being synthesised. The hypothetical adaptor molecule was later established to be a hitherto unknown nucleic acid, transfer RNA (tRNA). Development In 1953, English biophysicist Francis Crick and American biologist James Watson, working together at the Cavendish L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexander Dounce
Alexander Latham Dounce (December 7, 1909 – April 24, 1997) was an American professor of biochemistry. Among his fields of study were the isolation and purification of cellular organelles, protein crystallization, enzymes (specifically catalase), DNA binding proteins, and the chemical basis of protein synthesis. He also invented the Dounce homogenizer, which was named after him. Biography Alexander Dounce was born on December 7, 1909, in New York. He began his undergraduate studies at Hamilton College but later moved to Cornell University, where he also did his doctoral studies in the lab of James B. Sumner, a pioneer in protein crystallization. Dounce received his PhD in organic chemistry in 1935, the title of his thesis being "''Study of dihydrofurans and the dehydration rearrangement of 2,3-ethylenic 1,4-diols''". According to Marshall W. Nirenberg, another biochemist who knew Dounce personally, "during his ounce'sfinal doctoral exam when his doctoral committee got toge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University College London
, mottoeng = Let all come who by merit deserve the most reward , established = , type = Public research university , endowment = £143 million (2020) , budget = £1.544 billion (2019/20) , chancellor = Anne, Princess Royal(as Chancellor of the University of London) , provost = Michael Spence , head_label = Chair of the council , head = Victor L. L. Chu , free_label = Visitor , free = Sir Geoffrey Vos , academic_staff = 9,100 (2020/21) , administrative_staff = 5,855 (2020/21) , students = () , undergrad = () , postgrad = () , coordinates = , campus = Urban , city = London, England , affiliations = , colours = Purple and blue celeste , nickname ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Society For Experimental Biology
The Society for Experimental Biology is a learned society for animal, cell and plant biologists. It was founded in 1923 at Birkbeck College to "promote the art and science of experimental biology in all its branches". It aims to demonstrate the importance and impact of experimental biology research to the wider public and within the scientific community and to connect and support experimental biologists in their research and career development. The society has an international membership of approximately 1500, more than 20 scientific special interest groups and an outreach, education, and diversity (OED) group. Activities The main activities of the society are the organisation and sponsorship of scientific meetings, the publication of relevant research, and the promotion of development of experimental biologist through education, communication, and career development programmes. The society organises one large meeting each year, plus a number of smaller meetings. The main meeti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribosomes
Ribosomes ( ) are macromolecular machines, found within all cells, that perform biological protein synthesis (mRNA translation). Ribosomes link amino acids together in the order specified by the codons of messenger RNA (mRNA) molecules to form polypeptide chains. Ribosomes consist of two major components: the small and large ribosomal subunits. Each subunit consists of one or more ribosomal RNA (rRNA) molecules and many ribosomal proteins (RPs or r-proteins). The ribosomes and associated molecules are also known as the ''translational apparatus''. Overview The sequence of DNA that encodes the sequence of the amino acids in a protein is transcribed into a messenger RNA chain. Ribosomes bind to messenger RNAs and use their sequences for determining the correct sequence of amino acids to generate a given protein. Amino acids are selected and carried to the ribosome by transfer RNA (tRNA) molecules, which enter the ribosome and bind to the messenger RNA chain via an anti-cod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Code
The genetic code is the set of rules used by living cells to translate information encoded within genetic material ( DNA or RNA sequences of nucleotide triplets, or codons) into proteins. Translation is accomplished by the ribosome, which links proteinogenic amino acids in an order specified by messenger RNA (mRNA), using transfer RNA (tRNA) molecules to carry amino acids and to read the mRNA three nucleotides at a time. The genetic code is highly similar among all organisms and can be expressed in a simple table with 64 entries. The codons specify which amino acid will be added next during protein biosynthesis. With some exceptions, a three-nucleotide codon in a nucleic acid sequence specifies a single amino acid. The vast majority of genes are encoded with a single scheme (see the RNA codon table). That scheme is often referred to as the canonical or standard genetic code, or simply ''the'' genetic code, though variant codes (such as in mitochondria) exist. History Effor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lock And Key Model
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction rat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleobase
Nucleobases, also known as ''nitrogenous bases'' or often simply ''bases'', are nitrogen-containing biological compounds that form nucleosides, which, in turn, are components of nucleotides, with all of these monomers constituting the basic building blocks of nucleic acids. The ability of nucleobases to form base pairs and to stack one upon another leads directly to long-chain helical structures such as ribonucleic acid (RNA) and deoxyribonucleic acid (DNA). Five nucleobases—adenine (A), cytosine (C), guanine (G), thymine (T), and uracil (U)—are called ''primary'' or ''canonical''. They function as the fundamental units of the genetic code, with the bases A, G, C, and T being found in DNA while A, G, C, and U are found in RNA. Thymine and uracil are distinguished by merely the presence or absence of a methyl group on the fifth carbon (C5) of these heterocyclic six-membered rings. In addition, some viruses have aminoadenine (Z) instead of adenine. It differs in having an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
George Gamow
George Gamow (March 4, 1904 – August 19, 1968), born Georgiy Antonovich Gamov ( uk, Георгій Антонович Гамов, russian: Георгий Антонович Гамов), was a Russian-born Soviet and American polymath, theoretical physicist and cosmologist. He was an early advocate and developer of Lemaître's Big Bang theory. He discovered a theoretical explanation of alpha decay by quantum tunneling, invented the liquid drop model and the first mathematical model of the atomic nucleus, and worked on radioactive decay, star formation, stellar nucleosynthesis and Big Bang nucleosynthesis (which he collectively called nucleocosmogenesis), and molecular genetics. In his middle and late career, Gamow directed much of his attention to teaching and wrote popular books on science, including '' One Two Three... Infinity'' and the ''Mr Tompkins'' series of books (1939–1967). Some of his books are still in print more than a half-century after their original publicat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Martin David Kamen
Martin David Kamen (August 27, 1913, Toronto – August 31, 2002, Montecito, California) was an American chemist who, together with Sam Ruben, co-discovered the synthesis of the isotope carbon-14 on February 27, 1940, at the University of California Radiation Laboratory, Berkeley. He also confirmed that all of the oxygen released in photosynthesis comes from water, not carbon dioxide, in 1941. Kamen was the first to use carbon-14 to study a biochemical system, and his work revolutionized biochemistry and molecular biology, enabling scientists to trace a wide variety of biological reactions and processes. Despite being blacklisted for nearly a decade on suspicion of being a security risk, Kamen went on to receive the Albert Einstein World Award of Science in 1989, and the U.S. Department of Energy's 1995 Enrico Fermi award for lifetime scientific achievement. Early life and education Kamen was born on August 27, 1913, in Toronto, the son of Russian Jewish immigrants. He g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sol Spiegelman
Sol Spiegelman (December 14, 1914 – January 21, 1983) was an American molecular biologist. He developed the technique of nucleic acid hybridization, which helped to lay the groundwork for advances in recombinant DNA technology. Early life and education Spiegelman was born in Brooklyn, New York City in 1914. He attended the City College of New York and was initially interested in biology, but found the courses uninspiring and instead chose to focus on math and physics. During his undergraduate work he took a leave of absence to work in a biology laboratory, where he studied the genetics of bacteria. He graduated in 1939 with a bachelor's degree in mathematics. He then began his graduate studies at Columbia University in 1940, studying cellular physiology under the supervision of H.B. Steinbach. Spiegelman joined Steinbach in his move to Washington University two years later, and received his PhD from that institution in 1944. His graduate work focused on what was then k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
